The benefits of solar energy are clear to all. However, getting the right system size and choosing the right installer can be a little more complex. This is because there are a lot of options out there now.
To be confident that you’re making a sound investment, it’s important that you ask the right questions and understand the answers as best as you can. To help you along the way, we’ve gathered the key questions to ask your solar panel installer before you sign on the dotted line.
1. Does the quote include all installation costs?
Nobody likes hidden costs. That’s why it’s vital to get a clear breakdown of all costs involved in the installation process.
Make sure you ask for a detailed quote that includes material costs, labour costs and any other expenses such as grid connection fees or equipment hire like scaffolding.
A comprehensive quote should include:
- Cost of solar panels
- Inverter costs
- Mounting system, brackets and other hardware
- Labour costs
- Any necessary electrical upgrades
- Scaffolding or special equipment costs
Don’t be afraid to ask for clarification on any items you don’t understand. A reputable installer should be happy to explain each aspect of the quote in detail.
2. What consumer protection do you offer?
Consumer protection should be at the front of your mind when choosing a solar installer. This means you’re covered in case anything bad happens – unfortunately the solar industry has seen its fair share of companies going out of business, leaving customers without the guarantees and support they were promised.
Ben Price, co-founder of Heatable, a Which Trusted solar installer, says: “We understand the common concerns [on consumer protection] and that’s why Heatable are members of the Home Insulation & Energy Systems Contractors Scheme (HIES). This offers deposit and guarantee protection, ensuring that the investment is safeguarded, even if a company ceases trading before the work is completed. It also offers a robust framework that provides access to mediation and an independent ombudsman, ensuring that any issues are resolved fairly and efficiently.”
It’s also crucial to ensure your installer is accredited under the Microgeneration Certification Scheme (MCS). This scheme is designed to protect consumers by ensuring good standards of performance and that installers are technically safe and competent. MCS accreditation is also necessary for eligibility for the Smart Export Guarantee (SEG), which provides payments for electricity exported to the grid.
When discussing consumer protection, don’t hesitate to ask about the company’s insurance coverage. Make sure they have adequate insurance to cover any potential damages to your property during installation or any injuries that might occur on-site.
3. What are the warranties for the panels and the installation work?
Warranties are a vital aspect of your solar panel investment. As Ben Price from Heatable explains, “Warranties provide peace of mind, ensuring homeowners are covered if the panels or the installation have any defects or issues in the future.
“Ideally, you want the solar installer to offer a workmanship warranty too, this is separate to the solar panel manufacturer’s warranty and ensures the installer will fix or repair any issues that arise due to the installation itself. For example, Heatable offer a 24-month workmanship warranty for additional peace of mind.”
When discussing warranties, be sure to ask about both the manufacturer’s warranty on the panels and inverter, as well as the installer’s warranty on the installation work itself.
Understanding the coverage and duration of these warranties is essential for protecting your investment in the long term. Usually, solar panels come with a 25 year performance warranty, whilst inverters often have a 10 year warranty. However, these can vary, so it’s important to get the specifics for your system.
4. What solar panels and other equipment do you use?
The quality and efficiency of your solar panels and associated equipment can significantly impact the performance of your system.
Richard Bartlett, Co-Founder and CEO of GreenHearth, says: “Panels should be categorised as Tier 1”. This relates to the solar panel manufacturer and is designed to help investors assess the quality of the solar equipment used. However, it can also be used by consumers to assess quality.
When it comes to panels, they tend to be either monocrystalline, polycrystalline or thin-film panels. Monocrystalline panels are often the best quality, the most efficient, but also the most expensive.
In addition, “Inverters should have a 10+ year warranty and the fixing coming from a recognised company with a good warranty of around 10 years – we see this as an area that companies often try to economise on with low quality fixing systems.”
Ask your installer about the specific make and model of the panels they plan to use, as well as the inverter model. This information will help you research the equipment’s performance and reliability.
5. How does my current energy use impact the size and cost of the solar installation?
Understanding your home’s energy consumption is key in determining the right size for your solar panel system.
Ask your installer to review your energy bills and explain how they’ve used this information to size your system. They should be able to provide a clear explanation of how your current energy use translates into the recommended system size and expected energy production.
This is important as a larger solar panel system means higher upfront costs. On the flip side, they can often come with quicker payback periods depending on your energy use.
6. How much energy will the system produce?
The size of your solar panel system is measured in kilowatts (kW) or sometimes kilowatt peak (kWp). This ‘nameplate capacity’ indicates the maximum electrical power the system can generate under optimal conditions. However, the annual energy output, measured in kilowatt hours (kWh), is a more practical measure of what your system will actually produce over a year.
As a general rule of thumb, a 4kW system in the UK will generate anywhere from 3,650kWh per year (based on 2.5 hours of peak sun a day) to 5,840kWh/year (based on 4 hours of peak sun per day). However, this figure can and will vary based on factors such as panel orientation, tilt, shading and panel efficiency.
Ask your installer to provide both the kW rating of your proposed system and the estimated annual kWh production. This information will allow you to compare quotes more effectively and understand the potential savings on your energy bills.
7. What are the estimated savings I can make per year on my energy bill?
Ask your installer to provide a detailed estimate of your potential annual savings. This should be based on your current energy consumption, the proposed system size and local sunlight conditions.
Whilst actual savings may vary, this estimate can help you understand the potential financial benefits of your solar investment – this, alongside reducing your environmental impact, is likely to be one of your biggest drivers on installing solar.
Remember that savings can come from both reduced grid electricity use and payments received through the SEG for excess energy exported to the grid. Your installer should be able to provide estimates for both of these factors.
8. Have the orientation and tilt of the roof been considered?
The orientation and tilt of your roof play a significant role in the efficiency of your solar panel system. South-facing roofs are ideal, but south-east and south-west orientations can also be highly effective and just a few percentage points behind south-facing.
The optimal tilt angle is between 30 to 40 degrees – this aligns well with many standard UK roof pitches.
Ask your installer how they’ve factored your roof’s orientation and tilt into their system design. They should be able to explain how these factors might affect your system’s performance and whether any adjustments (such as tilt frames for flat roofs) are necessary.
9. Is my roof structurally sound and how will you attach the panels?
Before any installation can take place, you need to make sure your roof is in good condition and can support the additional weight of solar panels. Ask your installer about their assessment process for roof integrity, how they plan to attach the panels securely and how they prevent any rainwater from breaching where the brackets are mounted (if this involves drilling into the roof).
This question is also an opportunity to discuss any potential roof repairs or replacements that might be necessary before installation. It’s generally more cost-effective to address these issues before installing solar panels.
10. How long have you been in operation and have you done similar projects?
Experience matters when it comes to solar panel installation. As Richard Bartlett of GreenHearth advises: “Generally you should be looking for someone who has been operating for at least a couple of years to build a good track record and experience with happy customers.”
Ask about the company’s history, their experience with projects similar to yours, and if they can provide references or case studies. This information can give you confidence in their ability to handle your installation effectively.
11. Are you doing the installation work or are you subcontracting it out?
It’s important to know who will actually be carrying out the work on your property.
Richard Bartlett says, “There are a huge number of ‘installers’ who are in fact originators, taking a cut and passing the work on to a third party. If this is the case then you don’t know who is actually carrying out the work. The third party margin will either put the price up to the customer or mean that the people doing the work are working on a shoestring which may lead to short cuts.”
If the company does use subcontractors, ask about their vetting process and how they ensure quality control. It’s vital to know who will be responsible for the work and who to contact if any issues arise during or after installation.
12. What are your timeframes for installation?
You’ll want to have a good handle on the timeline of any solar panel installation so you can plan accordingly. Ask about the expected start date, how long the installation process takes and any factors that might affect the timeline.
Be sure to discuss any potential disruptions to your daily life during the installation process. A typical residential installation might take 1-3 days, but this can vary depending on the system size and complexity.
13. Does the solar array come with an energy management display system?
Many modern solar panel systems come with sophisticated monitoring systems that allow you to track your energy production in real-time. These systems can provide valuable insights into your energy usage and production, helping you optimise your consumption patterns.
Ask your installer about the monitoring options available. Some systems allow you to view data on a physical display in your home, whilst others offer smartphone apps or web portals for remote monitoring. Understanding how your system performs can help you maximise its benefits and quickly identify any potential issues.
For ultra-modern, smart homes, you’ll want to integrate your solar panels to a home energy management system, or HEMS. A HEMS brings together multiple smart devices and sources so you can manage all of your energy import and export from one place. These systems optimise energy use patterns, adjust device operation and can even choose when to sell energy to the grid for you.
14. Do you recommend battery storage?
Battery storage systems are becoming an ever important pairing with solar panels. This is because they can enhance the benefits of your solar panel installation by allowing you to store excess energy for use when your panels aren’t producing electricity (such as at night or on cloudy days). They can significantly increase your self-generated energy use, efficiency and have a short payback period.
They also come with an added cost of course, so it’s worth asking your installer whether they recommend a battery storage system for your specific situation, helping you decide if it’s a worthwhile investment for your home. They should be able to explain the potential benefits of battery storage, costs and help you calculate storage size required.
For more information, take a look at our post on solar panels with or without battery storage.
Final thoughts on solar panel installer questions
Installing solar panels is a significant investment in your home and your energy future. By asking the important questions, you’ll be better equipped to choose the right installer and system for your needs.
We recommend getting multiple quotes and comparing the responses you receive from different installers. Remember, a good installer will be happy to answer your questions thoroughly and provide clear, detailed information about their products and services. If they’re a bit cagey or defensive, it might be worth looking elsewhere.
Take your time to make an informed decision, and you’ll be well on your way to enjoying the benefits of clean, renewable solar energy in your home.